Mycotoxins are a group of secondary metabolites which are produced by various filamentous fungi that can cause a toxic response termed a mycotoxicosis, if ingested by higher vertebrates and other animals.
Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium species considered detrimental to human health and is classified as a possible human carcinogen. The recommended level for OTA in food for human consumption is 5 pg/kg for raw grain, 3 pg/kg for derived cereal products and 10 ilg/kg for dried vine fruits. The European Commission's Scientific Committee on Food has concluded that the intake of OTA should be reduced as far as possible to approximately 5 ng per kilogram of body weight per day (Scientific Committee for food 1996).
Cereals normally correspond to 50 to 80% of average consumer intake. OTA is found mainly in wheat and barley (Kuiper-Goodman 1996; Pittet 1998). It is also found in coffee (Burdaspal and Legarda, 1998; Dietrich et al., 1995, Jorgenson, 1998), wine (Burdaspal and Legarda, 1999; Visconti et al., 1999; Zimmerli and Dick, 1996), beer (Visconti et al., 2000), pork (Jorgenson, 1998; Wolff et al, 2000) and grapes.
Conventional methods for fungal detection and identification in a sample involve plating, incubation and identification based on morphological characteristics. These methods are time-consuming, labour intensive and require experienced personnel that may be lacking in many laboratories to interpret the results.
There is therefore a clear need for a more accessible and improved method for the detection and identification of the presence of OTA producing fungi present at even very low levels in a sample.